Malware" is any kind of software that's designed to harm a computer. Malware can steal sensitive information from your computer, gradually slow down your computer, or that will automatically plays, displays, or downloads advertisements on a computer.

Malware can get onto your computer in a number of different ways. Here are some common examples:

Downloading free software from the Internet that secretly contains malware

Downloading legitimate software that's secretly bundled with malware

Visiting a website that's infected with malware

Clicking a fake error message or pop-up window that starts a malware download

Opening an email attachment that contains malware

How to prevent malware

Keep your computer and software updated

Microsoft and Apple often release updates for their operating systems and it's a good idea to install these updates when they become available for your Windows and Mac computers. These updates often include fixes that can improve the security of your system. Some operating systems also offer automatic updates, so that you can automatically get updates soon after they're available.

Use a non-administrator account whenever possible

Most operating systems allow you to create multiple user accounts on your computer, so that different users can have different settings. These user accounts can also be set up to have different security settings. Doing this can help prevent malware from getting installed on your computer and making system-wide changes.

Think twice before clicking links or downloading anything

On the web, you should adopt a extra level of caution when entering unfamiliar websites that claim to offer free things. Downloads are one of the main ways people get malware, so remember to think twice about what you're downloading and where you're downloading it from.

Think twice before opening email attachments or images

f a random person sends you a box of chocolates in the mail, would you open it and scarf it down without any hesitation? Probably not. Similarly, you should be wary if a random person sends you a suspicious email containing attachments or images. Sometimes, those emails might just be spam, but other times, those emails might secretly contain harmful malware.

Don't trust pop-up windows that ask you to download software

When surfing the web, you might come across sites that show pop-up windows, making you believe your computer has been infected and asking you to download some software in order to protect yourself. Don't fall for this trick. Just close the pop-up window and make sure you don't click inside the pop-up window.

Be careful with file-sharing

Some sites and applications allow you to easily share files with other users. Many of these sites and applications offer little protection against malware. If you exchange or download files using these file-sharing methods, be on the lookout for malware. Malware can often be disguised as a popular movie, album, game, or program.

Use antivirus software

If you need to download something, you should use an antivirus program to scan that download for malware before opening it. Antivirus software also allows you to scan your entire computer for malware. It's a good idea to run regular scans of your computer to catch malware early and prevent it from spreading.